Documents disclosed under the 30-Year Rule reveal that the most controversial European issue of today - monetary union - was already being discussed at the highest levels of government in 1970 as the UK sought entry to the club.

When Edward Heath took power in June 1970, everyone knew that his main foreign policy goal was to succeed where Harold Wilson before him had failed, and gain a place for the UK in the European Economic Community.

The UK's attempts to join the European project had twice been brushed aside by the then six-strong community. But by 1970 the way appeared open.

Implications

Joining the Common Market, as it then was, had significant implications for Parliament and the UK's wider relationship with the Commonwealth nations.

But government papers disclosed for the first time reveal that the new Conservative prime minister's view was to get in, and get in fast.

PREM 15/62: Highlighted sovereignty issues

In July 1970, a memo to the prime minister from a cabinet office official put the point clearly.

"The longer these negotiations drag on, the less their prospect of success and the whole process is brought into public disrepute," wrote the official.

But crucially, the document indicated how officials were already thinking - and warning the politicians of the battles that could lie ahead.

"It may become necessary to project, some picture of the future development of the Community, if only because the very absence of such a picture gives rise to fears of the (supranational) unknown that are even now being exploited."

And in a hand-written note on top of the memo to Mr Heath, an official added: "Prime Minister, the ore important point is perhaps to consider whether we are equipped to think beyond the current "grocer's shop" stage.

We ought to give forethought to the implications for the political institutions and sovereignty."

In an interview for the programme, Sir Edward Heath said that as negotiations began, he saw problems in the UK losing momentum.

"The problem is explaining to the public the intricacies of joining another organisation which has had many years in building up its structure.

"They were not going to change their structure to take us in."

"Their attitude towards us"

But how were the other members regarding the UK's approach for membership?

FCO 30/770: Embassy advised on strategy

The UK's then ambassador in Paris, Christopher Soames (later Lord Soames), had a good idea of the French view, according to disclosed documents.

"We must not underestimate the impact which the Government's handling of the issues at home will have upon negotiations," he wrote to Foreign Secretary Sir Alec Douglas-Home.

"What has puzzled and dismayed French public opinion is the fact that so little has been done to far to try to evoke real enthusiasm in Britain for of Europe."

The ambassador said that the French saw the British (and particularly the previous Labour government) as being obsessed with the costs of entry.

"The figure we have cut so far is less that of a people determined to board the European train than that of a somewhat nervous passenger on the platform whose skirt has somehow got caught up in the door."

Difficulties at home

While Paris was urging an enthusiastic and visonary approach, domestic political considerations pulled the government in another direction.

Ministers and officials concurred that the negotiating stance had to avoid appearing too enthusiastic and "insufficiently hard-headed".

So was the government deliberately playing down future issues such as monetary union?

PREM 410/4: Werner Plan known to ministers

At the negotiating table, they could hardly be avoided as Brussels had already devised what became known as the Werner Plan, a proposal for monetary union.

According to the senior British officials who saw it, the plan "could imply the ultimate creation of a European federal state with a single currency.

"Everyone wanted to approach these monetary issues with extreme caution and the less they came out in the open, the better," Sir Crispin Tickell, one of the UK's negotiators at Brussels, told UK Confidential.

"But the argument in London was don't let's talk about this in public because we don't know what effects it would have on sterling.

"In other words the bread and butter issues are appropriate for a negotiation of this kind and when we're in, then we can discuss the longer-term questions."

For his part, Sir Edward Heath rejects suggestions that the government deliberately buried the prospect of monetary union as "propaganda".

"When I first negotiated with Harold Macmillan as prime minister, in my opening speech I said that our purpose was to join a community which was going to be full.

"I emphasised that the first part is not the question of trade and goods but the nature of the relationship between the countries and this was to be wholehearted.

"I've emphasised that point in every speech I've made."

Different course of action

And yet the same leading civil servants who predicted possible fallout from public discussion of Werner, proposed a different course of action.

"It will continue to be advantageous to HMG to avoid taking any attitude on the detail of the Werner proposals," they advised. In other words, don't say unless your asked.

But, speaking today, Sir Edward said that his government's approach to entering the EEC was less about pulling the wool over the eyes of the British public, and more about the pragmatic benefits of gaining entry and taking a stake in Europe's future.

"Sovereignty is something you can use for your own good," he told UK Confidential.

"By putting our share of sovereignty into the Community, we are able to share in all its benefits, otherwise we couldn't.

"The other members put their share of sovereignty into the community as well and we share that."

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